Add two classes [as yet unused] needed for upcoming IDB Blob support.

Source/platform/blink_platform.gypi

 {
   'variables': {
     'platform_files': [
       'AsyncFileSystemCallbacks.h',
       'CalculationValue.cpp',
       'CalculationValue.h',
       'CheckedInt.h',
       'Clock.cpp',
       'Clock.h',
       'ColorChooser.cpp',
@@ skipping 222 matching lines @@
       'audio/VectorMath.cpp',
       'audio/VectorMath.h',
       'audio/ZeroPole.cpp',
       'audio/ZeroPole.h',
       'audio/android/FFTFrameOpenMAXDLAndroid.cpp',
       'audio/ffmpeg/FFTFrameFFMPEG.cpp',
       'audio/ipp/FFTFrameIPP.cpp',
       'audio/mac/FFTFrameMac.cpp',
       'blob/BlobData.cpp',
       'blob/BlobData.h',
+      'blob/BlobInfo.h',

[jsbell, 2014/03/20 16:00:46]

So... with BlobDataHandle, BlobData, BlobDataItem and now BlobInfo it looks like
there may be some redundancy?

I haven't delved too deeply, but possibly there could be some cleanup there once
everything is in and tested.

[ericu, 2014/03/25 00:00:26]

BlobDataHandle manages lifetime.
BlobDataItem's the smallest fragment of a blob.
BlobData has the closest fit, but it's serving a different purpose.  It's not
clear to me that expanding it to handle the BlobInfo use cases as well, but it
might work; we can look at it later.

       'blob/BlobRegistry.cpp',
       'blob/BlobRegistry.h',
       'blob/BlobURL.cpp',
       'blob/BlobURL.h',
       'clipboard/ClipboardMimeTypes.cpp',
       'clipboard/ClipboardMimeTypes.h',
       'clipboard/ClipboardUtilities.cpp',
       'clipboard/ClipboardUtilities.h',
       'clipboard/ClipboardUtilitiesPosix.cpp',
       'clipboard/ClipboardUtilitiesWin.cpp',
       'exported/Platform.cpp',
       'exported/WebActiveGestureAnimation.cpp',
       'exported/WebActiveGestureAnimation.h',
       'exported/WebArrayBuffer.cpp',
       'exported/WebAudioBus.cpp',
       'exported/WebAudioDevice.cpp',
       'exported/WebBlobData.cpp',
+      'exported/WebBlobInfo.cpp',
       'exported/WebContentDecryptionModule.cpp',
       'exported/WebContentDecryptionModuleSession.cpp',
       'exported/WebCryptoAlgorithm.cpp',
       'exported/WebCryptoKeyAlgorithm.cpp',
       'exported/WebCryptoKey.cpp',
       'exported/WebCryptoResult.cpp',
       'exported/WebCursorInfo.cpp',
       'exported/WebData.cpp',
       'exported/WebDeviceMotionData.cpp',
       'exported/WebDeviceOrientationData.cpp',
@@ skipping 650 matching lines @@
       'graphics/ImageDecodingStoreTest.cpp',
       'graphics/ImageFrameGeneratorTest.cpp',
       'graphics/gpu/DrawingBufferTest.cpp',
       'graphics/test/MockImageDecoder.h',
       'graphics/test/MockWebGraphicsContext3D.h',
       'image-decoders/gif/GIFImageDecoderTest.cpp',
       'image-decoders/jpeg/JPEGImageDecoderTest.cpp',
     ],
   },
 }